Despite the fact that obesity is at epidemic proportions and costs US employers an estimated $78.5 billion annually; national data indicate that less than 25% of employers are offering disease management programs to address obesity. Effective weight loss programs that are adaptable to busy work environments and maintain employee interest are needed, but few rigorous tests of these programs have been attempted. In collaboration with the North Carolina Community College System, NC Blue Cross Blue Shield, and the State Teachers and Employee Medical Plan, we will conduct a three year group-randomized weight loss intervention study where 1300 overweight/obese employees nested within 13 community colleges will be randomly assigned to receive one of three promising, state-of-the-art, theory-linked interventions: Environment/Usual Care (E); Web-based Weight Loss Program + Environment (WEB+E) or Web + Environment +Incentives (WEB+E+I). College is the unit of randomization and intervention; employee is the unit of analysis. After formative research in Year 1 to adapt interventions for community college employees, we will rigorously test the effects of these interventions on 12-month weight loss (primary outcome). Weight will be measured at baseline, 3, 6, 9 and 12 months; and most secondary outcomes (weight loss behaviors, moderate-vigorous physical activity; total calories, percent body fat, fruit/vegetable intake, absenteeism, productivity, medical expenditures, and quality of life) will be assessed at baseline, 6 and 12 months; along with potential mediators/moderators of weight loss outcomes. Process tracking data will measure fidelity, dose delivered/received and acceptability/satisfaction with the interventions. Extensive cost- and cost-effectiveness analysis, including return on investment, will be undertaken. If proven effective, this strong partnership between community colleges, the State Health Plan, and the research team, will help guide program adoption and institutionalization/dissemination throughout the community college campus system.